DefDlgProc
The DefDlgProc
function carries out default message processing for a window procedure belonging
to an application-defined dialog box class.
LRESULT DefDlgProc(
|
HWND hDlg, |
// handle to dialog
box |
|
UINT Msg, |
// message |
|
WPARAM wParam, |
// first message
parameter |
|
LPARAM lParam |
// second message
parameter |
|
); |
|
Parameters
hDlg
Identifies
the dialog box.
Msg
Specifies the
message number.
wParam
Specifies
additional message-specific information.
lParam
Specifies
additional message-specific information.
Return Values
The return
value specifies the result of the message processing and depends on the message
sent.
Remarks
The DefDlgProc
function is the window procedure for the predefined class of dialog box. This
procedure provides internal processing for the dialog box by forwarding
messages to the dialog box procedure and carrying out default processing for
any messages that the dialog box procedure returns as FALSE. Applications that
create custom window procedures for their custom dialog boxes often use DefDlgProc
instead of the DefWindowProc
function to carry out default message processing.
Applications
create custom dialog box classes by filling a WNDCLASS structure with
appropriate information and registering the class with the RegisterClass
function. Some applications fill the structure by using the GetClassInfo
function, specifying the name of the predefined dialog box. In such cases, the
applications modify at least the lpszClassName member before
registering. In all cases, the cbWndExtra member of WNDCLASS for
a custom dialog box class must be set to at least DLGWINDOWEXTRA.
The DefDlgProc
function must not be called by a dialog box procedure; doing so results
in recursive execution.
See Also